Field
This application relates generally to communication and more specifically, but not exclusively, to fractional frequency reuse.
Introduction
A wireless communication network may be deployed to provide various types of services (e.g., voice, data, multimedia services, etc.) to users within a geographical area. In a typical implementation, macro access points (e.g., corresponding to different macro cells) are distributed throughout a network to provide wireless connectivity for access terminals (e.g., cell phones) that are operating within the geographical area served by the network.
In some networks, low-power access points (e.g., femto cells) are deployed to supplement conventional network access points (e.g., macro access points). For example, a low-power access point installed in a user's home or in an enterprise environment (e.g., commercial buildings) may provide voice and high speed data service for access terminals supporting cellular radio communication (e.g., CDMA, WCDMA, UMTS, LTE, etc.). In general, these low-power access points provide more robust coverage and higher throughput for access terminals in the vicinity of the low-power access points.
At a given point in time, an access terminal may be served by a given one of these access points. As the access terminal roams throughout the geographical area, the access terminal may move away from its serving access point and move closer to another access point. In addition, signal conditions within a given cell may change, whereby an access terminal may be better served by another access point. In these cases, to maintain mobility for the access terminal, the access terminal may be handed-over from its serving access point to the other access point.
In practice, issues may arise relating to mobility of an access terminal, particularly in the case where the network includes regions of densely populated low-power access points. A fast moving access terminal may frequently experience poor service due to signal conditions encountered at the cell edges of these access points. For example, an access terminal may experience radio link failure (RLF) with its serving cell before the access terminal can be handed-over to a neighboring cell.